Refactored lamexp_temp_folder2() function. This also fixes a potential deadlock at application when %TMP% points to an invalid folder. Now using separate locks for lamexp_temp_folder2() and lamexp_known_folder().

doc/Changelog.html

@@ -21,6 +21,7 @@ a:visited { color: #0000EE; }
 <li>Updated Qt runtime libraries to v4.8.5 (2013-05-31), compiled with MSVC 11.0
 <li>Updated FLAC encoder/decoder to v1.3.0 (2013-05-27), compiled with ICL 13.0
 <li>Updated Opus encoder/decoder libraries to v1.1.x and Opus-Tools to v0.1.6 (2013-06-17)
+<li>Fixed a potential deadlock during startup when %TMP% points to an invalid folder
 <li>Fixed a superfluous "beep" sound that appeared on application startup
 </ul><br>
 

src/Config.h

@@ -34,7 +34,7 @@
 #define VER_LAMEXP_MINOR_LO					8
 #define VER_LAMEXP_TYPE						Alpha
 #define VER_LAMEXP_PATCH					3
-#define VER_LAMEXP_BUILD					1298
+#define VER_LAMEXP_BUILD					1301
 #define VER_LAMEXP_CONFG					1288
 
 ///////////////////////////////////////////////////////////////////////////////

src/Dialog_SplashScreen.cpp

@@ -144,12 +144,14 @@ void SplashScreen::showSplash(QThread *thread)
 	//Loop while thread is still running
 	if(bool bIsRunning = THREAD_RUNNING(thread))
 	{
+		int deadlockCounter = 0;
 		while(bIsRunning)
 		{
 			loop->exec();
 			if(bIsRunning = THREAD_RUNNING(thread))
 			{
 				qWarning("Potential deadlock in initialization thread!");
+				if(++deadlockCounter >= 10) qFatal("Deadlock in initialization thread!");
 			}
 		}
 	}

src/Global.cpp

@@ -228,11 +228,18 @@ static const unsigned int g_lamexp_toolver_coreaudio = VER_LAMEXP_TOOL_COREAUDIO
 //Special folders
 static struct
 {
-	QString *temp;
 	QMap<size_t, QString> *knownFolders;
 	QReadWriteLock lock;
 }
-g_lamexp_folder;
+g_lamexp_known_folder;
+
+//%TEMP% folder
+static struct
+{
+	QString *path;
+	QReadWriteLock lock;
+}
+g_lamexp_temp_folder;
 
 //Tools
 static struct
@@ -1487,102 +1494,103 @@ QString lamexp_rand_str(void)
 	throw "The RegExp didn't match on the UUID string. This shouldn't happen ;-)";
 }
 
+
+/*
+ * Try to initialize the folder (with *write* access)
+ */
+static QString lamexp_try_init_folder(const QString &folderPath)
+{
+	bool success = false;
+
+	const QFileInfo folderInfo(folderPath);
+	const QDir folderDir(folderInfo.absoluteFilePath());
+
+	//Create folder, if it does *not* exist yet
+	if(!folderDir.exists())
+	{
+		folderDir.mkpath(".");
+	}
+
+	//Make sure folder exists now *and* is writable
+	if(folderDir.exists())
+	{
+		QFile testFile(folderDir.absoluteFilePath(QString("~%1.tmp").arg(lamexp_rand_str())));
+		if(testFile.open(QIODevice::ReadWrite))
+		{
+			const QByteArray testData = QByteArray("Lorem ipsum dolor sit amet, consectetur, adipisci velit!");
+			if(testFile.write(testData) >= strlen(testData))
+			{
+				success = true;
+				testFile.remove();
+			}
+			testFile.close();
+		}
+	}
+
+	return (success ? folderDir.canonicalPath() : QString());
+}
+
 /*
  * Get LameXP temp folder
  */
 const QString &lamexp_temp_folder2(void)
 {
-	QReadLocker readLock(&g_lamexp_folder.lock);
+	QReadLocker readLock(&g_lamexp_temp_folder.lock);
 
 	//Already initialized?
-	if(g_lamexp_folder.temp)
+	if(g_lamexp_temp_folder.path && (!g_lamexp_temp_folder.path->isEmpty()))
 	{
-		if(!g_lamexp_folder.temp->isEmpty())
+		if(QDir(*g_lamexp_temp_folder.path).exists())
 		{
-			if(QDir(*g_lamexp_folder.temp).exists())
+			return *g_lamexp_temp_folder.path;
-			{
-				return *g_lamexp_folder.temp;
-			}
 		}
 	}
-	
+
+	//Obtain the write lock to initilaize
 	readLock.unlock();
-	QWriteLocker writeLock(&g_lamexp_folder.lock);
+	QWriteLocker writeLock(&g_lamexp_temp_folder.lock);
 	
-	if(!g_lamexp_folder.temp)
+	//Still uninitilaized?
+	if(g_lamexp_temp_folder.path && (!g_lamexp_temp_folder.path->isEmpty()))
 	{
-		g_lamexp_folder.temp = new QString();
+		if(QDir(*g_lamexp_temp_folder.path).exists())
+		{
+			return *g_lamexp_temp_folder.path;
+		}
+	}
+
+	//Create the string, if not done yet
+	if(!g_lamexp_temp_folder.path)
+	{
+		g_lamexp_temp_folder.path = new QString();
 	}
 	
-	g_lamexp_folder.temp->clear();
+	g_lamexp_temp_folder.path->clear();
-
-	static const char *TEMP_STR = "Temp";
-	const QString WRITE_TEST_DATA = lamexp_rand_str();
-	const QString SUB_FOLDER = lamexp_rand_str();
 
 	//Try the %TMP% or %TEMP% directory first
-	QDir temp = QDir::temp();
+	QString tempPath = lamexp_try_init_folder(QDir::temp().absolutePath());
-	if(temp.exists())
+	if(!tempPath.isEmpty())
 	{
-		temp.mkdir(SUB_FOLDER);
+		(*g_lamexp_temp_folder.path) = lamexp_try_init_folder(QString("%1/%2").arg(tempPath, lamexp_rand_str()));
-		if(temp.cd(SUB_FOLDER) && temp.exists())
+	}
+
+	//Otherwise create TEMP folder in %LOCALAPPDATA%
+	if(g_lamexp_temp_folder.path->isEmpty())
+	{
+		tempPath = lamexp_try_init_folder(QString("%1/Temp").arg(lamexp_known_folder(lamexp_folder_localappdata)));
+		if(!tempPath.isEmpty())
 		{
-			QFile testFile(QString("%1/~%2.tmp").arg(temp.canonicalPath(), lamexp_rand_str()));
+			(*g_lamexp_temp_folder.path) = lamexp_try_init_folder(QString("%1/%2").arg(tempPath, lamexp_rand_str()));
-			if(testFile.open(QIODevice::ReadWrite))
-			{
-				if(testFile.write(WRITE_TEST_DATA.toLatin1().constData()) >= strlen(WRITE_TEST_DATA.toLatin1().constData()))
-				{
-					(*g_lamexp_folder.temp) = temp.canonicalPath();
-				}
-				testFile.remove();
-			}
-		}
-		if(!g_lamexp_folder.temp->isEmpty())
-		{
-			return *g_lamexp_folder.temp;
 		}
 	}
 
-	//Create TEMP folder in %LOCALAPPDATA%
+	//Failed to create TEMP folder?
-	QDir localAppData = QDir(lamexp_known_folder(lamexp_folder_localappdata));
+	if(g_lamexp_temp_folder.path->isEmpty())
-	if(!localAppData.path().isEmpty())
 	{
-		if(!localAppData.exists())
+		qFatal("Temporary directory could not be initialized !!!");
-		{
-			localAppData.mkpath(".");
-		}
-		if(localAppData.exists())
-		{
-			if(!localAppData.entryList(QDir::AllDirs).contains(TEMP_STR, Qt::CaseInsensitive))
-			{
-				localAppData.mkdir(TEMP_STR);
-			}
-			if(localAppData.cd(TEMP_STR) && localAppData.exists())
-			{
-				localAppData.mkdir(SUB_FOLDER);
-				if(localAppData.cd(SUB_FOLDER) && localAppData.exists())
-				{
-					QFile testFile(QString("%1/~%2.tmp").arg(localAppData.canonicalPath(), lamexp_rand_str()));
-					if(testFile.open(QIODevice::ReadWrite))
-					{
-						if(testFile.write(WRITE_TEST_DATA.toLatin1().constData()) >= strlen(WRITE_TEST_DATA.toLatin1().constData()))
-						{
-							(*g_lamexp_folder.temp) = localAppData.canonicalPath();
-						}
-						testFile.remove();
-					}
-				}
-			}
-		}
-		if(!g_lamexp_folder.temp->isEmpty())
-		{
-			return *g_lamexp_folder.temp;
-		}
 	}
-
+	
-	//Failed to create TEMP folder!
+	return *g_lamexp_temp_folder.path;
-	qFatal("Temporary directory could not be initialized!\n\nFirst attempt:\n%s\n\nSecond attempt:\n%s", temp.canonicalPath().toUtf8().constData(), localAppData.canonicalPath().toUtf8().constData());
-	return *g_lamexp_folder.temp;
 }
 
 /*
@@ -1908,7 +1916,7 @@ const QString &lamexp_known_folder(lamexp_known_folder_t folder_id)
 	static const GUID GUID_PROGRAM_FILES = {0x905e63b6,0xc1bf,0x494e,{0xb2,0x9c,0x65,0xb7,0x32,0xd3,0xd2,0x1a}};
 	static const GUID GUID_SYSTEM_FOLDER = {0x1AC14E77,0x02E7,0x4E5D,{0xB7,0x44,0x2E,0xB1,0xAE,0x51,0x98,0xB7}};
 
-	QReadLocker readLock(&g_lamexp_folder.lock);
+	QReadLocker readLock(&g_lamexp_known_folder.lock);
 
 	int folderCSIDL = -1;
 	GUID folderGUID = {0x0000,0x0000,0x0000,{0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00}};
@@ -1938,20 +1946,31 @@ const QString &lamexp_known_folder(lamexp_known_folder_t folder_id)
 	}
 
 	//Already in cache?
-	if(g_lamexp_folder.knownFolders)
+	if(g_lamexp_known_folder.knownFolders)
 	{
-		if(g_lamexp_folder.knownFolders->contains(folderCacheId))
+		if(g_lamexp_known_folder.knownFolders->contains(folderCacheId))
 		{
-			return (*g_lamexp_folder.knownFolders)[folderCacheId];
+			return (*g_lamexp_known_folder.knownFolders)[folderCacheId];
 		}
 	}
 
+	//Obtain write lock to initialize
 	readLock.unlock();
-	QWriteLocker writeLock(&g_lamexp_folder.lock);
+	QWriteLocker writeLock(&g_lamexp_known_folder.lock);
+
+	//Still not in cache?
+	if(g_lamexp_known_folder.knownFolders)
+	{
+		if(g_lamexp_known_folder.knownFolders->contains(folderCacheId))
+		{
+			return (*g_lamexp_known_folder.knownFolders)[folderCacheId];
+		}
+	}
 
 	static SHGetKnownFolderPathFun SHGetKnownFolderPathPtr = NULL;
 	static SHGetFolderPathFun SHGetFolderPathPtr = NULL;
 
+	//Lookup functions
 	if((!SHGetKnownFolderPathPtr) && (!SHGetFolderPathPtr))
 	{
 		QLibrary kernel32Lib("shell32.dll");
@@ -1964,6 +1983,7 @@ const QString &lamexp_known_folder(lamexp_known_folder_t folder_id)
 
 	QString folder;
 
+	//Now try to get the folder path!
 	if(SHGetKnownFolderPathPtr)
 	{
 		WCHAR *path = NULL;
@@ -2002,14 +2022,14 @@ const QString &lamexp_known_folder(lamexp_known_folder_t folder_id)
 	}
 
 	//Create cache
-	if(!g_lamexp_folder.knownFolders)
+	if(!g_lamexp_known_folder.knownFolders)
 	{
-		g_lamexp_folder.knownFolders = new QMap<size_t, QString>();
+		g_lamexp_known_folder.knownFolders = new QMap<size_t, QString>();
 	}
 
 	//Update cache
-	g_lamexp_folder.knownFolders->insert(folderCacheId, folder);
+	g_lamexp_known_folder.knownFolders->insert(folderCacheId, folder);
-	return (*g_lamexp_folder.knownFolders)[folderCacheId];
+	return (*g_lamexp_known_folder.knownFolders)[folderCacheId];
 }
 
 /*
@@ -2434,7 +2454,8 @@ extern "C"
 		LAMEXP_ZERO_MEMORY(g_lamexp_tools);
 		LAMEXP_ZERO_MEMORY(g_lamexp_currentTranslator);
 		LAMEXP_ZERO_MEMORY(g_lamexp_translation);
-		LAMEXP_ZERO_MEMORY(g_lamexp_folder);
+		LAMEXP_ZERO_MEMORY(g_lamexp_known_folder);
+		LAMEXP_ZERO_MEMORY(g_lamexp_temp_folder);
 		LAMEXP_ZERO_MEMORY(g_lamexp_ipc_ptr);
 		LAMEXP_ZERO_MEMORY(g_lamexp_os_version);
 		LAMEXP_ZERO_MEMORY(g_lamexp_themes_enabled);
@@ -2501,24 +2522,24 @@ void lamexp_finalization(void)
 	}
 	
 	//Delete temporary files
-	if(g_lamexp_folder.temp)
+	if(g_lamexp_temp_folder.path)
 	{
-		if(!g_lamexp_folder.temp->isEmpty())
+		if(!g_lamexp_temp_folder.path->isEmpty())
 		{
 			for(int i = 0; i < 100; i++)
 			{
-				if(lamexp_clean_folder(*g_lamexp_folder.temp))
+				if(lamexp_clean_folder(*g_lamexp_temp_folder.path))
 				{
 					break;
 				}
 				Sleep(125);
 			}
 		}
-		LAMEXP_DELETE(g_lamexp_folder.temp);
+		LAMEXP_DELETE(g_lamexp_temp_folder.path);
 	}
 
 	//Clear folder cache
-	LAMEXP_DELETE(g_lamexp_folder.knownFolders);
+	LAMEXP_DELETE(g_lamexp_known_folder.knownFolders);
 
 	//Clear languages
 	if(g_lamexp_currentTranslator.instance)

src/Thread_Initialization.cpp

@@ -297,6 +297,10 @@ void InitializationThread::run()
 		qWarning("Extracting tools took %.3f seconds -> probably slow realtime virus scanner.", delayExtract);
 		qWarning("Please report performance problems to your anti-virus developer !!!\n");
 	}
+	else
+	{
+		qDebug("Extracting the tools took %.3f seconds (OK).\n", delayExtract);
+	}
 
 	//Register all translations
 	initTranslations();